Anyone know about additional damage from a poison? I would assume you would have to reduce the additional damage included via the poison, but I just think the rule works weirdly in this situation.
I get how the rule works for damage accounting for how fast and powerful an arrow may be, and how that may make it more difficult to catch. However, an applied poison wouldn't make something more difficult to catch would it? Is there some rule I'm overlooking in regards to this?
The whole dealing damage on an attack that may not even hit is confusing me on this one tbh. Especially if poisons should only deal damage if it hits, and it has technically, but at the same time, it may not have.
I would probably rule that if you manage to catch the projectile (i.e. piercing damage is reduced to 0), no poison damage would be suffered. If, however, any damage from the initial hit remains, the poison would hit on top.
Anyone know about additional damage from a poison? I would assume you would have to reduce the additional damage included via the poison, but I just think the rule works weirdly in this situation.
I get how the rule works for damage accounting for how fast and powerful an arrow may be, and how that may make it more difficult to catch. However, an applied poison wouldn't make something more difficult to catch would it? Is there some rule I'm overlooking in regards to this?
The whole dealing damage on an attack that may not even hit is confusing me on this one tbh. Especially if poisons should only deal damage if it hits, and it has technically, but at the same time, it may not have.
There's really only one damage roll, whether there's poison or any other damage type included, right? The whole point of DM revolves around deflecting it in such a way as to take less-to-no damage, and the more damage there is to deflect, the harder it is to do. Avoiding damage from a poison, that has presumably resulted from an attack that has already 'hit', is also harder.
I can see how someone might make an argument for poisons that trigger on having taken damage not be included in the DM formula, but to be honest I still don't see how that would make a difference beyond resistance/immunity. If you're level 10 Monk then you're immune to poison damage, so that of course wouldn't be included in the DC for DM anyway. Otherwise, if you can't reduce the entire roll to zero, you still take at least one point of damage, which would presumably be of the projectile's damage. Beyond that minimum, it's up to the DM & player to figure out, but I'd probably just go with a ratio proportionate to the total damage taken pre-DM.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Anyone know about additional damage from a poison? I would assume you would have to reduce the additional damage included via the poison, but I just think the rule works weirdly in this situation.
I get how the rule works for damage accounting for how fast and powerful an arrow may be, and how that may make it more difficult to catch. However, an applied poison wouldn't make something more difficult to catch would it? Is there some rule I'm overlooking in regards to this?
The whole dealing damage on an attack that may not even hit is confusing me on this one tbh. Especially if poisons should only deal damage if it hits, and it has technically, but at the same time, it may not have.
There's really only one damage roll, whether there's poison or any other damage type included, right? The whole point of DM revolves around deflecting it in such a way as to take less-to-no damage, and the more damage there is to deflect, the harder it is to do. Avoiding damage from a poison, that has presumably resulted from an attack that has already 'hit', is also harder.
I can see how someone might make an argument for poisons that trigger on having taken damage not be included in the DM formula, but to be honest I still don't see how that would make a difference beyond resistance/immunity. If you're level 10 Monk then you're immune to poison damage, so that of course wouldn't be included in the DC for DM anyway. Otherwise, if you can't reduce the entire roll to zero, you still take at least one point of damage, which would presumably be of the projectile's damage. Beyond that minimum, it's up to the DM & player to figure out, but I'd probably just go with a ratio proportionate to the total damage taken pre-DM.
Except poison isn't usually a simple add on to the damage roll, it's usually an additional saving throw, meaning a separate damage roll. It probably shouldn't be included for deflect missiles except possibly if it's a contact poison (rare for weapon attacks) and the monk chose to catch the missile instead of simply knocking it aside with their weapon.
Anyone know about additional damage from a poison? I would assume you would have to reduce the additional damage included via the poison, but I just think the rule works weirdly in this situation.
I get how the rule works for damage accounting for how fast and powerful an arrow may be, and how that may make it more difficult to catch. However, an applied poison wouldn't make something more difficult to catch would it? Is there some rule I'm overlooking in regards to this?
The whole dealing damage on an attack that may not even hit is confusing me on this one tbh. Especially if poisons should only deal damage if it hits, and it has technically, but at the same time, it may not have.
There's really only one damage roll, whether there's poison or any other damage type included, right? The whole point of DM revolves around deflecting it in such a way as to take less-to-no damage, and the more damage there is to deflect, the harder it is to do. Avoiding damage from a poison, that has presumably resulted from an attack that has already 'hit', is also harder.
I can see how someone might make an argument for poisons that trigger on having taken damage not be included in the DM formula, but to be honest I still don't see how that would make a difference beyond resistance/immunity. If you're level 10 Monk then you're immune to poison damage, so that of course wouldn't be included in the DC for DM anyway. Otherwise, if you can't reduce the entire roll to zero, you still take at least one point of damage, which would presumably be of the projectile's damage. Beyond that minimum, it's up to the DM & player to figure out, but I'd probably just go with a ratio proportionate to the total damage taken pre-DM.
Except poison isn't usually a simple add on to the damage roll, it's usually an additional saving throw, meaning a separate damage roll. It probably shouldn't be included for deflect missiles except possibly if it's a contact poison (rare for weapon attacks) and the monk chose to catch the missile instead of simply knocking it aside with their weapon.
If it's a poison that activates by inflicted damage there is no reason for it to take affect because the condition of the poison working have not taken affect if you blocked all of the incoming damage assuming that their is some kind of save roll for the poison which there usually is but would not if it's all just part of the damage being dealt by the attack. So realistically If you can catch it and fire it back Then there is potential for actually poisoning who ever you shoot it at realistically. I admit I may be remembering wrong but I want to say there is a rule somewhere about this exact situation in fact and maybe somebody else can dig it up or correct me. I'm not in a position to find it myself currently (no access to books right now).
Interestingly however Sneak attack is different since it's automatic without it's own save and specifically added on to the attack made so even if you deflect them there is still a decent to good chance they would do damage because you'd have to block it all. Despite some technically coming from the arrow and some technically coming from the ability they are all entirely one without extra steps just extra conditions before firing to combine them.
We don't need to get into the granularity of specific types of applied poisons vs poison damage in general, or whether saves are involved, to understand how DM works because the question is mostly related to general rules.
Deflect Missiles comes in to play after you've been hit by a ranged attack, and all features that apply on a hit. At no point does DM ever turn a successful ranged attack into a miss. Even if you completely negate all damage from the attack, you were still hit. You were just hit by an attack that ended up not doing any damage to you.
If damage dice or modifiers are added to the damage roll as a result of a successful attack roll, that damage is damage from the attack itself, and is included when calculating the DC for Deflect Missiles. If a Warlock with a ranged pact weapon makes a successful attack roll against a Monk, and applies Eldritch Smite to the damage roll, that extra damage is included in the DM DC.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
The only reason that Deflect Missiles only comes into play after you've been hit is because you don't need to deflect a missile if it is not going to hit you. And yes, reducing the damage to zero does mean that you have taken a successful ranged attack hit and turned it into a miss.
The reduction in points (when you don't reduce the points to zero) is because you have deflected the missile away from hitting you squarely. Rather than taking a hit to the chest, you might get hit in the shoulder, or the arm, or maybe it just grazes your arm, causing 1 point of damage.
I would also argue that if the arrow is poisoned, you have two different damages from the arrow: the damage from an arrow (i.e. unpoisoned) and the damage from the poison itself. If you reduce the damage from the arrow to zero, I would say that it didn't hit you and, hence, you take zero damage from the poison.
And yes, reducing the damage to zero does mean that you have taken a successful ranged attack hit and turned it into a miss.
RAW, this is incorrect. It is a hit that deals zero damage. Any effects that trigger on a hit still apply, and any effects that trigger on a miss do not apply.
I would also argue that if the arrow is poisoned, you have two different damages from the arrow: the damage from an arrow (i.e. unpoisoned) and the damage from the poison itself. If you reduce the damage from the arrow to zero, I would say that it didn't hit you and, hence, you take zero damage from the poison.
This depends on the wording of the attack in question. In the case of an Assassin, a successful hit causes a separate saving throw against poison. Thus, the poison damage is separate from the arrow damage, and isn't affected by Deflect Missile. However, even if the monk reduces the weapon damage to zero and throws it back, they are still subject to the poison saving throw, as the attack did hit them.
In the case of something like a Yuan Ti Pureblood, their arrows deal 4 (1d6 + 1) piercing damage plus 7 (2d6) poison damage. This damage is all part of the weapon attack, so all of it is affected by Deflect Missiles, and must be completely reduced to 0 (poison damage included) before the monk can throw the projectile back.
As a house rule, I think it is reasonable to allow the monk to avoid the poison damage if they reduce the piercing damage to zero, but that would be a house rule. I'd also be careful about going overboard with it and avoiding ALL on hit effects.
And yes, reducing the damage to zero does mean that you have taken a successful ranged attack hit and turned it into a miss.
RAW, this is incorrect. It is a hit that deals zero damage. Any effects that trigger on a hit still apply, and any effects that trigger on a miss do not apply.
I would also argue that if the arrow is poisoned, you have two different damages from the arrow: the damage from an arrow (i.e. unpoisoned) and the damage from the poison itself. If you reduce the damage from the arrow to zero, I would say that it didn't hit you and, hence, you take zero damage from the poison.
This depends on the wording of the attack in question. In the case of an Assassin, a successful hit causes a separate saving throw against poison. Thus, the poison damage is separate from the arrow damage, and isn't affected by Deflect Missile. However, even if the monk reduces the weapon damage to zero and throws it back, they are still subject to the poison saving throw, as the attack did hit them.
In the case of something like a Yuan Ti Pureblood, their arrows deal 4 (1d6 + 1) piercing damage plus 7 (2d6) poison damage. This damage is all part of the weapon attack, so all of it is affected by Deflect Missiles, and must be completely reduced to 0 (poison damage included) before the monk can throw the projectile back.
As a house rule, I think it is reasonable to allow the monk to avoid the poison damage if they reduce the piercing damage to zero, but that would be a house rule. I'd also be careful about going overboard with it and avoiding ALL on hit effects.
Exactly. All that ever really needs to be determined is whether the triggering source for any/all damage is directly resulting from an attack roll or not.
Poison (or any) damage on hit? It's included in DM DC. You have factually taken all of that damage, just like if you took more piercing damage, but you have the opportunity to still mitigate it. Damage from a critical hit works the same way.
Deflect Missiles isn't meant to make a Monk immune to ranged attacks, although they do get poison damage immunity at level 10, and enemies with ranged attacks stronger than a basic Longbow are a real threat.
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You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
If you are going to talk RAW, perhaps you should take the time to read the rules and additional guidance offered by Wizards of Coast:
"Starting at 3rd level, you can use your reaction to deflect or catch the missile when you are hit by a ranged weapon attack. When you do so, the damage you take from the attack is reduced by 1d10 + your Dexterity modifier + your monk level.
If you reduce the damage to 0, you can catch the missile if it is small enough for you to hold in one hand and you have at least one hand free. If you catch a missile in this way, you can spend 1 ki point to make a ranged attack with the weapon or piece of ammunition you just caught, as part of the same reaction. You make this attack with proficiency, regardless of your weapon proficiencies, and the missile counts as a monk weapon for the attack, which has a normal range of 20 feet and a long range of 60 feet."
While that first sentence does seem to suggest that the monk is hit regardless of the outcome of the deflect missiles, the rest of the statement is not so clear. In the second paragraph, it says that the monk catches the missile if the damage is reduced to 0. A catch would presume that the missile didn't actually hit the monk.
In the "Sage Advice Compendium" available on the Wizards of the Coast webpage, there is the following statement: "This approach is all about what the designers meant when they wrote something. In a perfect world, RAW and RAI (rules as intended) align perfectly, but sometimes the words on the page don’t succeed at communicating the designers’ intent."
In other words, Wizards is acknowledging that there are situations where the rules are not always worded perfectly. Now, lets go back to the first sentence of the description of Deflect Missiles: "Starting at 3rd level, you can use your reaction to deflect or catch the missile when you are hit by a ranged weapon attack." They could have meant to say "When a dice roll indicates you would be hit by a ranged weapon attack." Not as elegent, but, a more direct meaning.
When mentioning that you can only CATCH the missile if it is small enough to be caught and the monk has a hand free. This suggests that the missile is deflected and doesn't hit the monk if those two conditions aren't met.
In this case, since the ability is actually called DEFLECT missiles, it is easy to see that the RAI is that an attack reduced to O results in the missile being either deflected or caught by the monk and does not hit.
I promise you, I've read the rules and guidance plenty. Let's not start belittling people here.
RAW, the attack is a hit and applies all effects that trigger on hit. We even get a nice sage advice clarification for the extremely similar Parry, where parrying an attack to 0 damage still will apply poison, as the attack is a hit. Parrying an attack to zero damage would normally be a miss in every traditional sense of the word, but mechanically it still functions as a hit.
Yes, sometimes RAW doesn't gel perfectly with how we think things should work, or even as designers initially intended. One of the wonderful things about DnD is that the designers encourage DMs to adapt and change rules wherever it makes sense or creates a more fun scenario. I do it plenty. In fact, I would likely play exactly as you described for poisoned arrows vs deflect missiles, at least for monsters like the Assassin.
But I think its important that when someone asks how a feature works on a forum, they are given the answer strictly according to the rules. Even when RAI and RAW clash, the designers tend to make the distinction clear when giving their advice. Then, the reader can decide whether or not they want to use those rules, or to make small changes to better support the game they wish to play. Knowing the correct rule and consciously changing or ignoring it is a lot more helpful than misinterpreting the rule and causing confusion or consistency issues down the line.
That answer about parry fits my argument much better than yours: "Drow poison in the DMG is delivered by piercing/slashing damage (0 dmg = 0 poison). Poison in the MM's drow is delivered by hitting." Notice that 0 Damage = 0 Poison, implying that the parry negates the hit.
Again, you don't seem to understand the sources you are citing.
Read the entire post. The player asks if reducing damage to zero will prevent poison from applying. Crawford says it depends on what kind of poison.
Drow poison, the item from the PHB, has a specific clause in it that states that you must do piercing (or slashing) damage in order to apply poison. Therefore, parry (and deflect missiles) will prevent the poison from applying if they manage to reduce the damage to 0. The damage is the delivery mechanism, and it doesn't care about a hit or miss.
Drow creatures from the MM just say that the poison is applied on a hit, and doesn't care about piercing or slashing damage. Even if parry reduces the damage to 0, the poison is still applied.
Edit: Here is a much more straightforward case - this only addresses poison laced arrows like the Yuan Ti, but is pretty cut and dry.
"Does a monk need to reduce both an arrows damage and poison when they use deflect missile? if it is lased with poison."
"RAW, yes. RAI, I'd cancel the poison damage and let monk catch it if the piercing damage is reduced to 0"
Not sure if this was answered as it seems to be a lot of focus on Poison, But what about damage from Sneak Attack? Is that counted toward the DM roll or is that applied only if there is still damage left from the weapons attack?
Not sure if this was answered as it seems to be a lot of focus on Poison, But what about damage from Sneak Attack? Is that counted toward the DM roll or is that applied only if there is still damage left from the weapons attack?
Sneak attack damage is applied to the attack itself, it isn't a separate roll which means it counts towards the DM missile roll.
Since the Critical Hit rules treat Sneak Attack as part of the attack's damage (see below), Deflect Missiles should interact in the same manner. You'd need to reduce the standard damage + Sneak Attack damage down to 0 before catching and throwing back the arrow.
When you score a critical hit, you get to roll extra dice for the attack’s damage against the target. Roll all of the attack’s damage dice twice and add them together. Then add any relevant modifiers as normal. To speed up play, you can roll all the damage dice at once. For example, if you score a critical hit with a dagger, roll 2d4 for the damage, rather than 1d4, and then add your relevant ability modifier. If the attack involves other damage dice, such as from the rogue’s Sneak Attack feature, you roll those dice twice as well.
What is the definition and example of physical missiles cause I just got into an argument about deflect missile and the dm say based on the discription it only works on magic missile
Deflect missiles doesn't work against magic missiles. They aren't physical. It works against arrows, thrown spears, sling stones, quarrels, darts, thrown daggers, etc.
The description of deflect missiles specifically states "when you are hit by a ranged weapon attack." Magic missile is a spell attack.
I would probably rule that if you manage to catch the projectile (i.e. piercing damage is reduced to 0), no poison damage would be suffered. If, however, any damage from the initial hit remains, the poison would hit on top.
There's really only one damage roll, whether there's poison or any other damage type included, right? The whole point of DM revolves around deflecting it in such a way as to take less-to-no damage, and the more damage there is to deflect, the harder it is to do. Avoiding damage from a poison, that has presumably resulted from an attack that has already 'hit', is also harder.
I can see how someone might make an argument for poisons that trigger on having taken damage not be included in the DM formula, but to be honest I still don't see how that would make a difference beyond resistance/immunity. If you're level 10 Monk then you're immune to poison damage, so that of course wouldn't be included in the DC for DM anyway. Otherwise, if you can't reduce the entire roll to zero, you still take at least one point of damage, which would presumably be of the projectile's damage. Beyond that minimum, it's up to the DM & player to figure out, but I'd probably just go with a ratio proportionate to the total damage taken pre-DM.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
Except poison isn't usually a simple add on to the damage roll, it's usually an additional saving throw, meaning a separate damage roll. It probably shouldn't be included for deflect missiles except possibly if it's a contact poison (rare for weapon attacks) and the monk chose to catch the missile instead of simply knocking it aside with their weapon.
If it's a poison that activates by inflicted damage there is no reason for it to take affect because the condition of the poison working have not taken affect if you blocked all of the incoming damage assuming that their is some kind of save roll for the poison which there usually is but would not if it's all just part of the damage being dealt by the attack. So realistically If you can catch it and fire it back Then there is potential for actually poisoning who ever you shoot it at realistically. I admit I may be remembering wrong but I want to say there is a rule somewhere about this exact situation in fact and maybe somebody else can dig it up or correct me. I'm not in a position to find it myself currently (no access to books right now).
Interestingly however Sneak attack is different since it's automatic without it's own save and specifically added on to the attack made so even if you deflect them there is still a decent to good chance they would do damage because you'd have to block it all. Despite some technically coming from the arrow and some technically coming from the ability they are all entirely one without extra steps just extra conditions before firing to combine them.
We don't need to get into the granularity of specific types of applied poisons vs poison damage in general, or whether saves are involved, to understand how DM works because the question is mostly related to general rules.
Deflect Missiles comes in to play after you've been hit by a ranged attack, and all features that apply on a hit. At no point does DM ever turn a successful ranged attack into a miss. Even if you completely negate all damage from the attack, you were still hit. You were just hit by an attack that ended up not doing any damage to you.
If damage dice or modifiers are added to the damage roll as a result of a successful attack roll, that damage is damage from the attack itself, and is included when calculating the DC for Deflect Missiles. If a Warlock with a ranged pact weapon makes a successful attack roll against a Monk, and applies Eldritch Smite to the damage roll, that extra damage is included in the DM DC.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
The only reason that Deflect Missiles only comes into play after you've been hit is because you don't need to deflect a missile if it is not going to hit you. And yes, reducing the damage to zero does mean that you have taken a successful ranged attack hit and turned it into a miss.
The reduction in points (when you don't reduce the points to zero) is because you have deflected the missile away from hitting you squarely. Rather than taking a hit to the chest, you might get hit in the shoulder, or the arm, or maybe it just grazes your arm, causing 1 point of damage.
I would also argue that if the arrow is poisoned, you have two different damages from the arrow: the damage from an arrow (i.e. unpoisoned) and the damage from the poison itself. If you reduce the damage from the arrow to zero, I would say that it didn't hit you and, hence, you take zero damage from the poison.
RAW, this is incorrect. It is a hit that deals zero damage. Any effects that trigger on a hit still apply, and any effects that trigger on a miss do not apply.
This depends on the wording of the attack in question. In the case of an Assassin, a successful hit causes a separate saving throw against poison. Thus, the poison damage is separate from the arrow damage, and isn't affected by Deflect Missile. However, even if the monk reduces the weapon damage to zero and throws it back, they are still subject to the poison saving throw, as the attack did hit them.
In the case of something like a Yuan Ti Pureblood, their arrows deal 4 (1d6 + 1) piercing damage plus 7 (2d6) poison damage. This damage is all part of the weapon attack, so all of it is affected by Deflect Missiles, and must be completely reduced to 0 (poison damage included) before the monk can throw the projectile back.
As a house rule, I think it is reasonable to allow the monk to avoid the poison damage if they reduce the piercing damage to zero, but that would be a house rule. I'd also be careful about going overboard with it and avoiding ALL on hit effects.
Exactly. All that ever really needs to be determined is whether the triggering source for any/all damage is directly resulting from an attack roll or not.
Poison (or any) damage on hit? It's included in DM DC. You have factually taken all of that damage, just like if you took more piercing damage, but you have the opportunity to still mitigate it. Damage from a critical hit works the same way.
Deflect Missiles isn't meant to make a Monk immune to ranged attacks, although they do get poison damage immunity at level 10, and enemies with ranged attacks stronger than a basic Longbow are a real threat.
You don't know what fear is until you've witnessed a drunk bird divebombing you while carrying a screaming Kobold throwing fire anywhere and everywhere.
If you are going to talk RAW, perhaps you should take the time to read the rules and additional guidance offered by Wizards of Coast:
"Starting at 3rd level, you can use your reaction to deflect or catch the missile when you are hit by a ranged weapon attack. When you do so, the damage you take from the attack is reduced by 1d10 + your Dexterity modifier + your monk level.
If you reduce the damage to 0, you can catch the missile if it is small enough for you to hold in one hand and you have at least one hand free. If you catch a missile in this way, you can spend 1 ki point to make a ranged attack with the weapon or piece of ammunition you just caught, as part of the same reaction. You make this attack with proficiency, regardless of your weapon proficiencies, and the missile counts as a monk weapon for the attack, which has a normal range of 20 feet and a long range of 60 feet."
While that first sentence does seem to suggest that the monk is hit regardless of the outcome of the deflect missiles, the rest of the statement is not so clear. In the second paragraph, it says that the monk catches the missile if the damage is reduced to 0. A catch would presume that the missile didn't actually hit the monk.
In the "Sage Advice Compendium" available on the Wizards of the Coast webpage, there is the following statement: "This approach is all about what the designers
meant when they wrote something. In a perfect world, RAW and RAI (rules as intended) align perfectly, but sometimes the words on the page don’t succeed at communicating the designers’ intent."
In other words, Wizards is acknowledging that there are situations where the rules are not always worded perfectly. Now, lets go back to the first sentence of the description of Deflect Missiles: "Starting at 3rd level, you can use your reaction to deflect or catch the missile when you are hit by a ranged weapon attack." They could have meant to say "When a dice roll indicates you would be hit by a ranged weapon attack." Not as elegent, but, a more direct meaning.
When mentioning that you can only CATCH the missile if it is small enough to be caught and the monk has a hand free. This suggests that the missile is deflected and doesn't hit the monk if those two conditions aren't met.
In this case, since the ability is actually called DEFLECT missiles, it is easy to see that the RAI is that an attack reduced to O results in the missile being either deflected or caught by the monk and does not hit.
I promise you, I've read the rules and guidance plenty. Let's not start belittling people here.
RAW, the attack is a hit and applies all effects that trigger on hit. We even get a nice sage advice clarification for the extremely similar Parry, where parrying an attack to 0 damage still will apply poison, as the attack is a hit. Parrying an attack to zero damage would normally be a miss in every traditional sense of the word, but mechanically it still functions as a hit.
Yes, sometimes RAW doesn't gel perfectly with how we think things should work, or even as designers initially intended. One of the wonderful things about DnD is that the designers encourage DMs to adapt and change rules wherever it makes sense or creates a more fun scenario. I do it plenty. In fact, I would likely play exactly as you described for poisoned arrows vs deflect missiles, at least for monsters like the Assassin.
But I think its important that when someone asks how a feature works on a forum, they are given the answer strictly according to the rules. Even when RAI and RAW clash, the designers tend to make the distinction clear when giving their advice. Then, the reader can decide whether or not they want to use those rules, or to make small changes to better support the game they wish to play. Knowing the correct rule and consciously changing or ignoring it is a lot more helpful than misinterpreting the rule and causing confusion or consistency issues down the line.
That answer about parry fits my argument much better than yours: "Drow poison in the DMG is delivered by piercing/slashing damage (0 dmg = 0 poison). Poison in the MM's drow is delivered by hitting." Notice that 0 Damage = 0 Poison, implying that the parry negates the hit.
Again, you don't seem to understand the sources you are citing.
Read the entire post. The player asks if reducing damage to zero will prevent poison from applying. Crawford says it depends on what kind of poison.
Drow poison, the item from the PHB, has a specific clause in it that states that you must do piercing (or slashing) damage in order to apply poison. Therefore, parry (and deflect missiles) will prevent the poison from applying if they manage to reduce the damage to 0. The damage is the delivery mechanism, and it doesn't care about a hit or miss.
Drow creatures from the MM just say that the poison is applied on a hit, and doesn't care about piercing or slashing damage. Even if parry reduces the damage to 0, the poison is still applied.
Edit: Here is a much more straightforward case - this only addresses poison laced arrows like the Yuan Ti, but is pretty cut and dry.
"Does a monk need to reduce both an arrows damage and poison when they use deflect missile? if it is lased with poison."
"RAW, yes. RAI, I'd cancel the poison damage and let monk catch it if the piercing damage is reduced to 0"
Not sure if this was answered as it seems to be a lot of focus on Poison, But what about damage from Sneak Attack? Is that counted toward the DM roll or is that applied only if there is still damage left from the weapons attack?
Sneak attack damage is applied to the attack itself, it isn't a separate roll which means it counts towards the DM missile roll.
Since the Critical Hit rules treat Sneak Attack as part of the attack's damage (see below), Deflect Missiles should interact in the same manner. You'd need to reduce the standard damage + Sneak Attack damage down to 0 before catching and throwing back the arrow.
What is the definition and example of physical missiles cause I just got into an argument about deflect missile and the dm say based on the discription it only works on magic missile
Deflect missiles doesn't work against magic missiles. They aren't physical. It works against arrows, thrown spears, sling stones, quarrels, darts, thrown daggers, etc.
The description of deflect missiles specifically states "when you are hit by a ranged weapon attack." Magic missile is a spell attack.
It is only phisical attacks because you can not hold an element
Just a grung lover